Imaging diagnostics by combining contrast agents

Abstract

The present invention relates to the use of a combination of several contrast agents having different properties with respect to imaging representation.

Claims

1. A polymodal method for imaging a lesion in a patient comprising: administering to said patient: an extracellular contrast medium (ECCM) selected from the group consisting of: gadobutrol, gadopentetatic acid or a salt thereof, gadobenic acid, gadodiamide, gadoxetic acid/disodium salt and gadoteridol; and a lesion-specific contrast medium (LSCM) selected from the group consisting of: .sup.99mTc-Medronat, .sup.99mTc-Sestamibi, .sup.99mTc-ECD, .sup.99mTc-MAG3, .sup.111In-DTPY-octreotide, .sup.111In-DTPA-octreotate, .sup.18F-fluordesoxyglucose, .sup.18F-dopamine, .sup.18F-L-DOPA, .sup.18F-fluorcholine, .sup.18F-fluormethylethylcholin, .sup.18F-fluordihydro-testosterone, .sup.68Ga-NODAGATOC and .sup.68Ga-DOTATOC, wherein the LSCM is enriched in the lesion 10 minutes after administration to said patient and is retained in the lesion for at least 1 hour; and subjecting the patient to polymodal imaging wherein at least two different imaging modalities are used to provide at least two different imaging signals which are immediately interpolated by a fusion method of the at least two different imaging modalities, wherein the at least two different imaging modalities are selected from: PET-MRI and SPECT-MRT; and wherein either: a. the ECCM and the LSCM are administered consecutively; or b. the ECCM and the LSCM are administered simultaneously.

2. The method of claim 1, wherein the polymodal imaging uses the combination of the imaging modalities: MRI imaging and .sup.18F-PET tracer imaging.

3. The method of claim 1, wherein the polymodal imaging uses the combination of the imaging modalities: MRT-optical imaging and SPECT-MRT imaging.

4. The method of claim 1, wherein the ECCM and the LSCM are administered to said patient consecutively with a time delay between administrations of 10 to 30 minutes.

5. The method of claim 1, wherein the ECCM and the LSCM are administered to said patient consecutively with a time delay between administrations of 10 to 15 minutes.

6. The method of claim 1, wherein the ECCM and LSCM are administered consecutively.

7. The method of claim 1, wherein the ECCM and LSCM are administered simultaneously.

8. A kit for conducting the method of claim 1, comprising: an extracellular contrast medium (ECCM) selected from the group consisting of: gadobutrol, gadopentetatic acid or a salt thereof, gadobenic acid, gadodiamide, gadoxetic acid/disodium salt and gadoteridol; and a lesion-specific contrast medium (LSCM) selected from the group consisting of: .sup.99mTc-Medronat, .sup.99mTc-Sestamibi, .sup.99mTc-ECD, .sup.99mTc-MAG3, .sup.111In-DTPY-octreotide, .sup.111In-DTPA-octreotate, .sup.18F-fluordesoxyglucose, .sup.18F-dopamine, .sup.18F-L-DOPA, .sup.18F-fluorcholine, .sup.18F-fluormethylethylcholin, .sup.18F-fluordihydro-testosterone, .sup.68Ga-NODAGATOC and .sup.68Ga-DOTATOC, which LSCM is enriched in the lesion 10 minutes after administration to said patient and is retained in the lesion for at least 1 hour; wherein the kit is provided in a form suitable for simultaneous or consecutive administration of the ECCM and the LSCM to said patient.

Description

EXAMPLES

Example 1

(1) A middle-aged patient. This patient suffered from a malignant brain tumour, a glioblastoma, and was treated for it. Apart from an operation, the treatment also included radiotherapy of the brain with increased radiation in the former operation area using directed stereotactic techniques. After about six months, the patient's initially good clinical situation deteriorated. The clinical examination results in presumed tumour growth recurring.

(2) Diagnostic imaging by means of a PET-CT device combination can illustrate tumours both by using X-ray contrast agents and by using PET isotopes. With an extracellular CT contrast agent such as e.g. Ultravist a region accumulating contrast agent inhomogeneously in the region of the former tumour bed can be seen. With regard to differential diagnosis, apart from a tumour recurringa local relapse, cell death caused by high radiationradionecrosisis possible.

(3) The PET isotope .sup.18F-fluordeoxyglucose (FDG) as LSCM, which was injected simultaneously, provides the explanation for the differential diagnosis: the missing concentration of the LSCM in the cells of the region, which, in the CT, had shown a concentration of ECCM, proves the presence of radionecrosis. Further therapy consists in the administration of corticoids; the patient's prognosis is clearly better than in the case of a local relapse being present.

Example 2

(4) A patient, typically between 50 and 70 years of age, is admitted to hospital for further diagnosis and therapy due to blood deposits in the stool. The coloscopy carried out showed a malign tumour of the colon. During the ultrasound scan of the liver, which was also carried out, an individual, defined focus was found in the right hepatic lobe which lead to the presumption of a metastasis in the liver, a liver metastasis.

(5) The magnetoresonance tomography which was carried out, first, with an extracellular contrast agent (EECM, e.g. Magnevist), then directly followed by a lesion-specific contrast agent (LSCM, e.g. Resovist), confirmed, in the first step, the presence of a liver focus in the right hepatic lobe by means of ECCM. Differentiation of the type of tumour, however, is not possible. In this case, only the accumulation of the tumour with the LSCM showed that the cells of this dimension are liver cells and not tumour cells. Thus, metastasis of the colon tumour could be excluded, the diagnosis of a benign simple hemangioma of the liver could be secured by the combined contrast agents examination. The patient is subjected to a normal tumour operation of the colon.

Example 3

(6) A patient, typically in his late 50 s or early 60 s with a history of a recent heart attack is now being investigated for viable myocardium before cardiac bypass surgery. The patient's history includes a low grade nicotine abuse 20 years ago with overall eight pack-years exposure and a history of tuberculosis during adolescence. Previous diagnostic coronary angiography has revealed stenoses in the coronary arteries. PET imaging with use of F.sup.18-FDG as radiotracer revealed viable myocardium with the possibility to improve cardiac function with a revascularization procedure. Coincidentally an increased tracer uptake was seen during cardiac PET imaging in the left upper lobe of the lung, being consistent with cancer or infectious disease.

(7) A targeted contrast enhanced high-resolution thin slice computed tomography scan was performed in the upper lung lobes showing a well enhancing, approximately 2 cm measuring lesion. The high resolution thin slice images clearly showed a solid appearance of the tumor and very thin streaky structures surrounding the tumor in a radiate appearance, being typical for spiculae of a lung cancer. The combination of contrast enhancement in the solid lesion and the speculated appearance of the tumor secured the diagnosis of a small lung cancer.

(8) The entire disclosure of all applications, patents and publications, cited herein and of corresponding application No. 07110922.7 EP, filed Jun. 22, 2007, and PCT/EP2008/057886, filed Dec. 22, 2008, are incorporated by reference herein.